restrictive lungdiseases

Restrictive Diseases

Dr.CSBR.Prasad, M.D.

Chronic restrictive diseases

Restrictive diseases due to chest wall disorders

Restriction due to interstitial and infiltrative

diseases.

Restrictive - chest wall disorder

1. Kyphoscoliosis

2. Ankylosing spondilosis

3. Poliomyelitis

4. Severe obesity

5. Pleural diseases

Interstitial and infiltrative diseases

1. Pneumoconiosis

2. Immunologic lung diseases

3. Collagen vascular diseases

4. Sarcoidosis

Infiltrative - Radiologic term

• Chest radiograph - ground glass shadow

• Diffuse infiltration by nodules/lines

Clinical features

1. Dyspnoea

2. Tachypnoea

3. Cyanosis

4. No wheezing

Pneumoconiosis

• Lung disease caused by inhalation of dust

• Synonyms:

• Dust diseases

• Occupational lung diseases

• Dusts –Inert

Predispose to TB

Predispose to neoplasia

Factors determining - disease

1. Size / shape of particles

2. Solubility

3. Amount of dust retained in lungs

4. Effect of other irritants - ex Smoke

5. Host factors:

Clearance mechanism

Immune status

Size of dust

• Particles larger than 5µm may reach

– Terminal airway

– Ingestion by alveolar macrophage

• Smaller than 1µm may

– Reach alveoli

– Stimulate macrophage

– Result in fibrosis

In the nose, the hair at the external

nares filter out the larger particles,

trapping almost all particles larger than

5µm.

In the trachea and bronchi, 90% of the

particles larger than 3-5µm are caught.

Particles between 0.5 and 2µm reach

the alveolar ducts and alveoli.

Solubility and cytotoxicity

• Smaller particles:

– Pulmonary fluid

– Rapid toxic levels

– Cause acute lung injury

• Larger particles:

– Resist dissolution

– Persist in lung for years

– Evoke fibrosis ex silicosis

Physiochemical reactivity

• Quartz particles

• Direct injury to tissue and cell membrane

• Can trigger proinflammatory / profibrosing

reaction

Systemic response

• Particles reach LN by macrophages

• Initiate immune response / amplifies local

reaction

• Particles translocate to blood

• Evokes systemic inflammation.

Host tissue response

1. Fibrous nodules ex coal workers

pneumoconiosis, silicosis.

2. Interstitial fibrosis ex asbestosis.

3. Hypersensitivity ex.berylliosis.

Pneumoconiosis

(inorganic dusts)

• Coal dust

• Silica

• Asbestose

• Berylium

• Iron oxide

• Simple coal w p

• PMF

• Caplan’s syndrome

• Silicosis

• Caplan’s syndrome

• Asbestosis

• Pleural disease

• Pleural tumors

• Beryliosis

• Pulmonary siderosis

Pneumoconiosis

(biologic dusts)

• Mouldy hay

• Bagasse

• Cotton, flax, hempdust

• Bird droppings

• Mushroom compost dust

• Mouldey barley, malt dust

• Mouldy maple bark

• Silage fermentation

• Farmers’ lung

• Bagassosis

• Byssinosis

• Bird breeders disease

• Mushroom workers lung

• Malt workers lung

• Maple-bark disease

• Silo fillers’ disease

One form of hypersensitivity pneumonitis is known as farmer's lung - the farmer

inhales thermophilic actinomycetes in moldy hay that set off the reaction

"silo filler's disease" which is an acute chemical pneumonitis due to toxic

gases released from fermenting silage into the atmosphere inside the silo

Coal workers’s pneumoconiosis

1. Asymptomatic

2. Simple coal worker’s pneumoconiosis

3. Complicated CWP (progressive CWP)

Complicated CWP [PMF]

• Confluence of fibrosing reaction in lung

that is a complication of any

pneumoconiosis

• Common in CWP

• Can also be seen in silicosis

Anthracosis

• Coal - Innocuous

• Common in urban dwellers/smokers

• Carbon pigment in lung, lymphatics, LN

• Autopsy: linear streaks and aggregates in

pul. lymphatics, LNs

Simple CWP

• Coal macule: 1 to 2 mm, carbon laden macrophages

• Coal nodules: larger than macule, contain delicate collagen fibres

• Upper lobes, upper zones of lower lobes heavily involved

• Located adjacent to resp bronchioles-initial dust deposition site-centrilobular emphysema

Complicated CWP (PMF)

In a background of simple CWP

Over years

Intensely blackened scars

Larger than 2 cms

May be upto 10 cms

Multiple,bilateral,involve upper,post region

Micro: dense collagen, pigment,

necrotic centre,with local ischemia

Caplan syndrome (Rheumatoid pneumoconiosis)

• Development of rheumatoid arthritis in

CWP, silicosis, asbestosis

• Gross; round, firm nodules with central

necrosis, cavitation or calcification

• Micro: central zone of dust laden fibrinoid

necrosis enclosed by palisading

fibroblasts and mononuclear cells

Clinical features

• Cough with jet black sputum

• Dyspnoea

• Pul-HT, cor pulmonale

• TB and RA are more common in miners

• Increased risk for Ca. stomach

• Bronchogenic .ca is rare

Figure 15-18 Progressive massive

fibrosis superimposed on coal

workers' pneumoconiosis. The large,

blackened scars are located

principally in the upper lobe. Note the

extensions of scars into surrounding

parenchyma and retraction of

adjacent pleura.

"coal worker's pneumoconiosis"

Silicosis Knife grinders lung

Silicosis knife grinders lung

• Silica (silicon dioxide)

• Caused by inhalation of crystaline silica

• Presents after decades of exposure

• Slowly progressing nodular, fibrosing

pneumoconiosis

Acute silicosis

• Heavy exposure over months to few years

• Generalized accumulation of

lipoproteinaceous material within alveoli

• Morphologically identical to alveolar

proteinosis.

Chronic silicosis

Characterized by formation of small

collagenous silicotic nodules

Occupations - Silicosis

• Miners

• Quarry workers

• Tunnelers

• Sand blasters

• Grinders

• Ceramic workers

• Foundry workers

• Silica abrasive manufacturers

• Exposure to pencil

• Slate

• Agate grinding

Silica – Physical forms

Crystalline forms

• Quartz

• Crystobalite

• Tridymite

• Are fibrogenic

Amorphous forms

• Talc

• Vermiculite

• Mica

• Less fibrogenic

IARC pointed out that only crystalline form is actually carcinogenic

Pathogenesis - Silicosis

• Silica - macrophage ingestion - direct toxic effect

• Silica particles - activation and release of mediators by viable macrophages

• IL-1, TNF, fibronectin, lipidmediators, oxygen derived free radicles, fibrogenic cytokines

• Mixed with other minerals, quartz has less fibrogenic effect. ex: hematite.

Gross pathology

• Silicotic lung studded with well

circumscribed hard, fibrotic nodules,1 to 5

mm in diameters

• Scattered throughout the lung

• Simultaneous deposition of coal dust with

calcification

• Pleura thickened, adherent to chest wall

• Similar nodules in LN, pleura

Gross pathology contd…,

• X ray nodular lesions - egg shell shadows

• Lesion – necrosis, cavitation

• Complicated by TB, rheumatoid

pneumoconiosis.

Egg shell calcification

FIGURE 15-18

Advanced silicosis

Scarring has contracted

the upper lobe into a

small dark mass (arrow).

Note the dense pleural

thickening.

Microscopy of silicosis

• Nodular lesions- concentric layers of

hyalinised collagen surrounded by dense

capsule of more condensed collagen

• Polarising microscopy --- birefringent silica

particles.

Figure 15-19 Advanced silicosis seen on transection of lung. Scarring has

contracted the upper lobe into a small dark mass (arrow). Note the dense

pleural thickening.

Figure 15-20 Several coalescent collagenous silicotic nodules.

Figure 15-20 Several coalescent collagenous silicotic nodules.

Pneumoconiosis: polarized light microscopy - silica crystals.

Here are seen bright white crystals of varying sizes.

Bright white collections of polarizable crystals are seen here, but are diffuse and centered

around vascular spaces. This is the lung of a patient with a long history of intravenous drug use

Clinical features-silicosis

Asymptomatic- routine chest x ray

X ray- fine nodularity in upper zones

Pulm functions –normal/mildly affected.

Slow to kill but impaired pulm fn severely limits

activity.

Depresses CMI

Increased susceptibility to TB

Crystalline silica - occupational source of

carcinogen.

E N D

Contact:

Dr.CSBR.Prasad, M.D.,

Associate Professor,

Deptt. of Pathology,

Sri Devaraj Urs Medical College,

Kolar-563101,

Karnataka,

INDIA.

CSBRPRASAD@REDIFFMAIL.COM